LOW-GRADE PAPILLARY ADENOCARCINOMA: A RARE ENTITY

Abstract

Introduction Low-grade papillary adenocarcinoma (LGPA) of the minor salivary glands is uncommon, which is noted to occur after 40 years of age with a male/female ratio of 2:1. Adenocarcinoma in this site includes salivary and nonsalivary types pathologically. The prevalence of LGPA is 17%, which is often poorly recognized and misdiagnosed, as it has a greater potential for local recurrence with evidence of regional metastasis, and only a few cases are reported in the literature. LGPA represents a relatively rare histologic variant of polymorphous low-grade adenocarcinoma. Case Presentation A 50-year-old female patient reported a complaint of a swelling in the posterior part of the hard palate that was associated with pain of 1-year duration. On examination, a mobile submucosal swelling of 1-cm size was noted in the posterior part of the hard palate laterally on the left side, and wide excision of the lesion was performed. On histologic examination, the lesional tissue exhibited extensive well-defined papillary arrangement of tumor cells that had a columnar appearance. The lesion was interpreted as LGPA on histologic examination, which was followed by immunohistochemistry to confirm the diagnosis. She is disease-free over a period of 2 years, and follow-up is being continued to monitor for development of recurrence. Conclusion A rare case of LGPA is reported for its diagnostic challenge; the lesion has a biological tendency to develop local recurrence and regional metastasis. Low-grade papillary adenocarcinoma (LGPA) of the minor salivary glands is uncommon, which is noted to occur after 40 years of age with a male/female ratio of 2:1. Adenocarcinoma in this site includes salivary and nonsalivary types pathologically. The prevalence of LGPA is 17%, which is often poorly recognized and misdiagnosed, as it has a greater potential for local recurrence with evidence of regional metastasis, and only a few cases are reported in the literature. LGPA represents a relatively rare histologic variant of polymorphous low-grade adenocarcinoma. A 50-year-old female patient reported a complaint of a swelling in the posterior part of the hard palate that was associated with pain of 1-year duration. On examination, a mobile submucosal swelling of 1-cm size was noted in the posterior part of the hard palate laterally on the left side, and wide excision of the lesion was performed. On histologic examination, the lesional tissue exhibited extensive well-defined papillary arrangement of tumor cells that had a columnar appearance. The lesion was interpreted as LGPA on histologic examination, which was followed by immunohistochemistry to confirm the diagnosis. She is disease-free over a period of 2 years, and follow-up is being continued to monitor for development of recurrence. A rare case of LGPA is reported for its diagnostic challenge; the lesion has a biological tendency to develop local recurrence and regional metastasis.